CVE-2023-46976
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary commands on TOTOLINK A3300R routers by injecting malicious commands into the file_name parameter during firmware upload. Attackers can gain full control of affected devices, potentially compromising entire networks. All users of vulnerable TOTOLINK A3300R routers are affected.
💻 Affected Systems
- TOTOLINK A3300R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device takeover leading to network compromise, data exfiltration, lateral movement to other systems, and persistent backdoor installation.
Likely Case
Router compromise allowing traffic interception, DNS hijacking, credential theft, and use as attack platform against internal network.
If Mitigated
Limited impact if device is isolated, has strict network segmentation, and command injection attempts are blocked by WAF or IPS.
🎯 Exploit Status
Public exploit code available in GitHub repository. Simple HTTP POST request with command injection payload.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: Not available
Restart Required: No
Instructions:
1. Check TOTOLINK website for firmware updates
2. Download latest firmware
3. Access router web interface
4. Navigate to System Tools > Firmware Upgrade
5. Upload new firmware file
6. Wait for automatic reboot
🔧 Temporary Workarounds
Disable Web Management Interface
allPrevent access to vulnerable interface by disabling web management or restricting access
Access router CLI via SSH/Telnet
Disable web interface in configuration
Network Segmentation
allIsolate router management interface from untrusted networks
Configure firewall rules to restrict access to router management IP:port
🧯 If You Can't Patch
- Block access to router web interface from untrusted networks using firewall rules
- Monitor for unusual outbound connections or command execution attempts from router
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface under System Status > Firmware VersionCheck Version:
curl -s http://router-ip/cgi-bin/luci/ | grep firmwareVerify Fix Applied:
Verify firmware version has changed from vulnerable version📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /cgi-bin/luci/ with shell metacharacters in parameters
- Command execution attempts in system logs
Network Indicators:
- HTTP POST requests containing shell commands (;, |, &, $()) to router management interface
- Unexpected outbound connections from router
SIEM Query:
source="router_logs" AND (url="/cgi-bin/luci/" AND method="POST" AND (param="file_name" AND value="*;*" OR value="*|*" OR value="*&*" OR value="*$(*"))